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Tubby2
20th November 2007, 12:02 PM
Gday all,
I've been trolling thru the threads here on what to use and how to seal a deck and found Jim's post here (http://www.woodworkforums.com/showpost.php?p=512077&postcount=12) to be straight to the point.
I will be using the Spa & Deck Merbau

I've just about finished my third deck around the house and will soon be ready to seal all 3. The first deck I finished about 2 months ago and I can see a few boards that arent exactly smooth. One board in particular is really bad. As this board is in the middle of the deck on my front porch I will be replacing it.
My question is will I need to wait for the replacement board to whether for another 2-3 months? How picky should I be as to replacing other boards that arent smooth? Will these boards stand out more or less when they have been sealed? When they are wet it all looks the same, but when dry the imperfections stand out quite a bit.

Cheers

oohsam
20th November 2007, 01:29 PM
I have the same problem but I plan to do nothing about it. Just clean it with deck cleaner, karcher it once or twice (thanks to the water tank!) wait to dry and then oil it.
Not really fussed about the rough bits to tell u the truth.

jimj
21st November 2007, 07:00 AM
Dear Tubby,

I agree with Oosham. If your decking is that new then it will be fine to coat it now even with the new replacement board. It normally takes about 12-18 months of full daily sun before the surface starts to degrade to the point of making the timber feel a little rough across the grain. Merbau has a lot of tannin so I would do as Oosham suggests use some Powerlift or napisan apply on wet deck, leave for 10 minutes and thouroughly rinse. You can use a high pressure cleaner but it will not require more than 500 psi pressure. I would then use S&D prep which is Oxalic acid based. This will add a bit of brightness to the timber although the change is not that visibly dramatic. It also helps with the surface PH rebalance and tends to open the timber pores at the surface.It is applied to a wet deck ,leave 10 minutes and rinse off. I use a Rotowash scrubbing machine to scrub after each of these stages but the bottom line is when the deck is all clean and just wet with water if it looks stunning and has the WOW factor you are ready. You said you are using S&D so you can go straight into coating as the 1st coat goes onto wet timber. If you are using other coating products then you will need to wait for the timber to be totally dry. When I am cleaning a deck in prepration for a coating I often think it is a shame to put anything on the timber (even S&D) as the water alone gives the best look . Unfortunately the water dries out in minutes and even if it would last it has no pigments to block UV. I have removed nearly all products that are on the shelf at the paint stores. Some are good and others are just plain shockers but from what I have discovered first hand it is the Sun that causes the most breakdown and degradation. Most products continue to look fairly good as long as it is under roofline and blocking harsh sun. The issue is you get a gradual deteriation from great next to the house to stuffed on the edge. The challenge always remains as to how to keep it all looking fairly similar. Maybe the real answer is to do tiles or concrete. Sorry for the ramble my brain just went into cruise mode.

Jimj www.restore-a-deck.com.au

Dr - 307
21st November 2007, 07:17 AM
Jim,

I have been swayed into using S & D. Coating a brand new deck I understand will leave me some grain. What about in 12 to 18 months time? What is the prep required and will the subsequent coating hide even more grain to give the boards a 'painted over look' or do you 'Powerlift' the original S & D off and start from scratch. It looks like the owner of the job I'm about to start will want me to come back and do his re-coating when it is time so I want to be able to tell him what re-coating will involve.

Awaiting your reply,
Dr - 307.:cool: